Copper Loading-Controlled Selective Synthesis of 2,5-Bis(trifluoromethyl) and Monotrifluoromethyl-Substituted Oxazoles
Wei Wu, Zipeng Zhang, Jialong Li, Jianrong Xia, Xiaoyan Han, Zhiqiang Weng
Abstract
A general domino annulation reaction of sulfonylmethyl isocyanide with trifluoroacetic anhydride in the presence of copper chloride as an additive is developed. The reaction affords 2,5-bis(trifluoromethyl)oxazoles in modest to good yields under mild conditions. A wide variety of sulfonylmethyl isocyanide and perfluorocarboxylic anhydride substrates are amenable to this transformation. Under a higher copper salt loading conditions, the reaction led to the formation of monotrifluoromethyl-substituted oxazole product.
Topics & Concepts
Trifluoroacetic anhydrideOxazoleIsocyanideTrifluoromethylChemistryAnnulationCopperOrganic chemistryChlorideCombinatorial chemistryPolymer chemistryCatalysisAlkylFluorine in Organic ChemistryCyclopropane Reaction MechanismsCatalytic C–H Functionalization Methods